In 1991 the Glaxo Group's turnover in its business, now wholly devoted to the discovery, development, manufacture and sales of prescription medicines, was £3,397m and profits (before tax) were £1,283m. Over the last two decades remarkable and mainly self-generated growth has made Glaxo the largest pharmaceutical company in Britain and taken the company to second place in the world league of the industry. Glaxo's operations and sales extend across the world with more than 80 per cent (87 per cent in fact, when the UK is included) of turnover arising in the developed countries of Western Europe and North America.

The group's competitors, the multinational pharmaceutical corporations, have varied origins but those of Glaxo must be among the most unusual. The entry into the dried milk business of the Nathans, a small Jewish family firm of merchants in New Zealand, came about by serendipity rather than deliberate intent. It was the determination of one member of that family, Alec Nathan, which kept and developed Glaxo babyfood as part of the Nathan business. In the two decades after 1918, the discoveries made by nutritional researchers took the Nathans into vitamin manufacture in order to strengthen the Glaxo range of products.

At the same time the company developed its international operations and Glaxo products were sold, and some manufactured, not only in the company's traditional spheres of interest, Australia and New Zealand, but also in India, Africa, Europe and North and South America.